The present invention relates to slide closures for joining a variety of substrates and, more particularly, to slide closures for joining overlapping substrate edges having touch fasteners such as VELCRO thereon.
Numerous slide closures are known in the art for joining panels of flexible material, such as the opposed fabric panels joined by a zipper. Such slide closures are particularly useful for joining flexible material because they are designed to channel the two panels of material toward each other as they move along the opposed edges being joined. Another common example of slide closure is that found on plastic food storage bags. Such a slide closure channels the two aligned open edges of the bag toward each other and forces a rib on one edge into a complementary channel on the other edge in a dovetail arrangement.
Zippers, both metallic and plastic, are the slide closures of choice for garments and other fabric applications. Conventional zippers provide meshing teeth that relatively securely hold the two edges together. Of course, everyone has experienced zippers that bind due to material that catches in the teeth, or because one or more teeth become distorted. Another drawback with zippers is the potential for the meshing teeth to disengage which may prevent the slide closure from moving back across the affected area.
Because of the drawbacks associated with conventional slide closures, there is a need for an improved slide closure that reduces the potential for binding and is more forgiving when the edges that are joined together are inadvertently pulled apart.
The present invention provides a slide closure for joining complementary touch fasteners, comprising a slide closure body having channels opening on opposite sides for receiving overlapping edges of substrates having complementary touch fasteners thereon. The slide closure body includes first and second closing surfaces facing each other that converge toward one another to a nip defining a gap with a dimension sufficiently small to bring the first and second touch fasteners into engagement. The slide closure body is configured to move in one direction along the overlapping substrate edges and bring the edges together such that the complementary touch fasteners engage.
Preferably, each of the complementary touch fasteners has a width, the slide closure further comprising structure that connects the first and second closing surfaces including a spanning member having opposed faces. The structure and closing surfaces define the two channels each open to receive one of the substrates from one side of the slide closure. The channels having a width such that at least some of the widths of the first and second touch fasteners overlap between the closing surfaces and diverge around the opposed faces of the spanning member. In one embodiment, both the first and second closing surfaces are angled with respect to the directions in which the slide closure body moves, the convergence of the first and second closing surfaces compressing and engaging the complementary touch fasteners. Alternatively, only the first facing surface is angled with respect to the directions in which the slide closure body moves, the second facing surface being oriented generally parallel to the directions in which the slide closure body moves, the convergence of the first and second closing surfaces compressing and engaging the complementary touch fasteners.
In accordance with one preferred construction of the slide fastener, the first facing surface is defined on an inner surface of a first closing arm, and the second facing surface is defined on an inner surface of a second closing arm. Each of the first and second closing arms has a width substantially the same as the width of the spanning member, wherein each of the first and second closing arms attaches on a fixed side to the spanning member and is cantilevered across the width of the slide closure so that its inner surface partly defines one of the channels. The slide closure of further may include a first side wall attached to a first side of the spanning member and to the fixed side of the first closing arm, and a second side wall attached to a second side of the spanning member and to the fixed side of the second closing arm. The slide closure thus generally defines a Z-shape from the first closing arm through the first side wall across the spanning member through the second side wall and through the second closing arm.
In one aspect of the invention, the first and second closing surfaces are biased toward one another so that the nip gap is minimized. For example, the first and second closing surfaces may be formed separately from each other and from the spanning member, the slide closure including at least one spring biasing the first and second closing surfaces toward one another so that the nip gap is minimized. Desirably, the first and second closing surfaces are each formed on a closing arm having a side wall at one side, wherein the closing arms extend generally parallel to one another with the side walls disposed on opposite sides of the slide closure. Each side wall extends toward the opposite closing arm, and wherein portions of both side walls are aligned and each includes a hinge in which one side of the spanning member pivots. The spring is thus arranged to pivot the closing arms about the spanning member so that the nip gap is minimized.
The substrates may be provided with raised features, and the slide closure includes guide grooves for receiving the raised features and channeling the substrates therethrough.
The slide closure body may be configured to move in the direction along the overlapping substrate edges opposite the closing direction and separate the edges such that the complementary touch fasteners disengage. To do so, the slide fastener desirably has structure thereon that connects the first and second closing surfaces including a spanning member. The structure and closing surfaces define the two channels each open to receive one of the substrates from one side of the slide closure. The channels having a width such that at least some of the widths of the first and second touch fasteners overlap between the closing surfaces and diverge around the spanning member. The spanning member has a first separating surface, a second separating surface, and a nose in between the two separating surfaces, the nose pointing toward the nip. The spanning member is therefore adapted to cleave and separate the engaged touch fasteners when the slide closure body is moved in the opposite direction along the overlapping substrate edges.
Alternatively, the slide closure body may be configured to move in the both directions along the overlapping substrate edges and bring the edges together such that the complementary touch fasteners engage. In this construction, the first and second closing surfaces define a first pair of closing surfaces converging to a first nip. The slide closure body further includes a second pair of closing surfaces that converge toward one another to a second nip defining a gap with a dimension sufficiently small to bring the first and second touch fasteners into engagement.
In accordance with another aspect of the invention, a system for fastening a first touch fastener to a second touch fastener is provided, comprising a first substrate having a first elongate touch fastener along one edge, a second substrate having a second elongate touch fastener complementary to the first touch fastener, and a slide closure body having channels for receiving the substrates such that the first touch fastener faces the second touch fastener. The slide closure body is configured to move in one direction along the substrates and bring them together such that the complementary touch fasteners engage. The first and second substrates may comprise lengths of flexible sheet material, or the first substrate comprises a first length of flexible sheet material, and the second substrate comprises a rigid material.